chore: apply Claude setup improvements

- Expand permissions.allow (git, node, npm, npx, ls, cat, Read, Edit, Write, Glob, Grep) to reduce approval prompts
- Set CLAUDE_ECC_MODE=standard in env for consistent hook profile
- Gate stop-hook-git-check.sh behind ECC_GIT_CHECK=1 to prevent blocking mid-session
- Add project-level Node.js rules for ECC repo (stack, file conventions, hook dev standards)
- observe.sh confirmed already async — no change needed

https://claude.ai/code/session_014SqRA9y6HwVVPGeSCJfwVF

.claude/rules/node.md

@@ -0,0 +1,47 @@
+# Node.js Rules for everything-claude-code
+
+> Project-specific rules for the ECC codebase. Extends common rules.
+
+## Stack
+
+- **Runtime**: Node.js >=18 (no transpilation, plain CommonJS)
+- **Test runner**: `node tests/run-all.js` — individual files via `node tests/**/*.test.js`
+- **Linter**: ESLint (`@eslint/js`, flat config)
+- **Coverage**: c8
+- **Lint**: markdownlint-cli for `.md` files
+
+## File Conventions
+
+- `scripts/` — Node.js utilities, hooks. CommonJS (`require`/`module.exports`)
+- `agents/`, `commands/`, `skills/`, `rules/` — Markdown with YAML frontmatter
+- `tests/` — Mirror the `scripts/` structure. Test files named `*.test.js`
+- File naming: **lowercase with hyphens** (e.g. `session-start.js`, `post-edit-format.js`)
+
+## Code Style
+
+- CommonJS only — no ESM (`import`/`export`) unless file ends in `.mjs`
+- No TypeScript — plain `.js` throughout
+- Prefer `const` over `let`; never `var`
+- Keep hook scripts under 200 lines — extract helpers to `scripts/lib/`
+- All hooks must `exit 0` on non-critical errors (never block tool execution unexpectedly)
+
+## Hook Development
+
+- Hook scripts receive JSON on stdin — always `const input = JSON.parse(fs.readFileSync(0, 'utf8'))`
+- Async hooks: mark `"async": true` in `settings.json` with a timeout ≤30s
+- Blocking hooks (PreToolUse, stop): keep fast (<200ms) — no network calls
+- Use `run-with-flags.js` wrapper for all hooks so `CLAUDE_ECC_MODE` gating works
+- Always exit 0 on parse errors; log to stderr with `[HookName]` prefix
+
+## Testing Requirements
+
+- Run `node tests/run-all.js` before committing
+- New scripts in `scripts/lib/` require a matching test in `tests/lib/`
+- New hooks require at least one integration test in `tests/hooks/`
+
+## Markdown / Agent Files
+
+- Agents: YAML frontmatter with `name`, `description`, `tools`, `model`
+- Skills: sections — When to Use, How It Works, Examples
+- Commands: `description:` frontmatter line required
+- Run `npx markdownlint-cli '**/*.md' --ignore node_modules` before committing